The present invention relates to a device and a method for dispensing liquids.
Liquids consumed by individuals as well as liquids used for industrial and agricultural purposes are commonly stored in bottles or other containers that are sealed with a cap. Aliquots of liquids are removed from the containers by removing the cap and transferring the aliquot out of the container. The liquid aliquot may be transferred by methods that include pouring the liquid out of the container and siphoning the liquid.
In many instances, storing liquids in a cap sealed container has wasted the liquids. In particular, the stored liquids have been wasted because the liquids degrade with repeated removal of the cap and removal of aliquots of the liquid.
Some liquids such as carbonated beverages degrade by losing carbonation and becoming flat tasting with repeated removal and replacement of the cap of the beverage container. The beverages lose carbonation because carbon dioxide escapes from the bottle when the cap is removed and the beverage aliquot is poured from the bottle. The escaped carbon dioxide had formed a head of carbon dioxide vapor over the beverage, pressurizing the beverage. When the cap is re-secured onto the bottle, an equilibrium of carbon dioxide concentration between a liquid beverage phase and the vapor phase is re-established within the bottle. This equilibrium is re-established when carbon dioxide is transferred from the liquid beverage phase to the vapor phase over the liquid beverage in order to compensate for a reduction in liquid volume in the bottle. When the bottle is opened again, the carbon dioxide in the vapor phase escapes from the bottle. The transfer of carbon dioxide from the liquid to the vapor and escape of carbon dioxide from the bottle causes the liquid beverage to become flat tasting.
Other liquids stored in sealed containers degrade as a consequence of contamination by airborne microbes that are introduced when the liquids are exposed to air by a removal of a bottle cap and by transferring liquid out of the container. These liquids include media for growing and maintaining cell lines. These liquids also include biodegradable liquid foods such as cranberry juice.
Brown, U.S. Pat. No. 4,194,653, describes a soft drink dispenser utilizing the vapor pressure of carbon dioxide of a carbonated beverage within a container for transferring the beverage out of the container. The dispensing device includes a valve having a main valve body with a valve seat, an adaptor for detachably coupling the valve to the container and an elongated tube in self sealing engagement with the adaptor. The valve also includes a valve stem movably mounted within a channel formed in the valve body and a discharge spout in communication with the channel.
In a rest position, the valve stem is positioned on the valve seat. The valve stem includes a face in contact with the valve seat that blocks soft drink flow in a rest position and that permits soft drink flow when a force is applied to the valve stem of the valve. The force causes the valve stem to compress a spring, positioned concentrically about the valve stem. The force and the resulting compression of the spring results in the valve stem face separating from the valve seat. The separation allows liquid in the container to be forced by the pressure of carbonation through the elongated tube and out a discharge spout. The device described in the Brown patent requires pressure from carbon dioxide to transfer liquid from the inside of the container to the outside.
One solution that limits the degradation of liquids including carbonated beverages, cell line growth media and liquid foods has included storing the liquids in containers having a size of one liter or less. This solution is based on an assumption that the cap of a smaller container will not be removed enough times to cause an excessive loss of carbon dioxide or to inoculate the liquid with an airborne microbe. This solution has, however, caused another problem of inefficient and wasteful use of materials used to make the large quantity of smaller containers.